Only cache template digests if config.cache_template_loading

since ActionView::Resolver.caching is set to the same value as config.cache_template_loading
only cache template digests if config.cache_template_loading is not falsy
fixes issues #10752 and #10791

3 files changed, 24 insertions, 5 deletions

diff --git a/actionview/CHANGELOG.md b/actionview/CHANGELOG.md
index 98b78a7114..8fdbe15dee 100644
--- a/actionview/CHANGELOG.md
+++ b/actionview/CHANGELOG.md
@@ -1,3 +1,9 @@
+*   Only cache template digests if config.cache_template_loading, since
+    ActionView::Resolver.caching is set to the same value as
+    config.cache_template_loading
+
+    *Josh Lauer* *Justin Ridgewell*
+
 *   Added an `extname` hash option for `javascript_include_tag` method.
 
     Before:
diff --git a/actionview/lib/action_view/digestor.rb b/actionview/lib/action_view/digestor.rb
index 64239c81b2..95c3200c81 100644
--- a/actionview/lib/action_view/digestor.rb
+++ b/actionview/lib/action_view/digestor.rb
@@ -32,9 +32,13 @@ module ActionView
           Digestor
         end
 
-        @@cache[cache_key] = digest = klass.new(name, format, finder, options).digest # Store the actual digest
-      ensure
-        @@cache.delete_pair(cache_key, false) if pre_stored && !digest # something went wrong, make sure not to corrupt the @@cache
+        # Store the actual digest if config.cache_template_loading is true
+        klass.new(name, format, finder, options).digest.tap do |digest|
+          @@cache[cache_key] = digest if ActionView::Resolver.caching?
+        end
+      rescue Exception
+        @@cache.delete_pair(cache_key, false) if pre_stored # something went wrong, make sure not to corrupt the @@cache
+        raise
       end
     end
 
diff --git a/actionview/test/template/digestor_test.rb b/actionview/test/template/digestor_test.rb
index 67e3775f28..c6608e214a 100644
--- a/actionview/test/template/digestor_test.rb
+++ b/actionview/test/template/digestor_test.rb
@@ -184,6 +184,15 @@ class TemplateDigestorTest < ActionView::TestCase
     assert_not_equal digest_phone, digest_fridge_phone
   end
 
+  def test_cache_template_loading
+    resolver_before = ActionView::Resolver.caching
+    ActionView::Resolver.caching = false
+    assert_digest_difference("messages/edit", true) do
+      change_template("comments/_comment")
+    end
+    ActionView::Resolver.caching = resolver_before
+  end
+
   private
     def assert_logged(message)
       old_logger = ActionView::Base.logger
@@ -200,9 +209,9 @@ class TemplateDigestorTest < ActionView::TestCase
       end
     end
 
-    def assert_digest_difference(template_name)
+    def assert_digest_difference(template_name, persistent = false)
       previous_digest = digest(template_name)
-      ActionView::Digestor.cache.clear
+      ActionView::Digestor.cache.clear unless persistent
 
       yield